This proposal aims to utilize recombinant DNA technology to identify the genes encoding species-specific immunoreactive proteins of C. pneumoniae, and to evaluate the utility of the corresponding recombinant antigens for the serologic diagnosis of C. pneumoniae. The long term objective is to develop a novel ELISA and or a blot product. This product will be based on identified species-specific recombinant antigens leading to an inexpensive reliable and easy to interpret serodiagnostic test for human C. pneumoniae infection. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE